Beginner's Guide to Crystal Reports, Part I: Winforms

This parameter's screen was generated dynamically just by reading the .rpt file!

Introduction

The company I own provides custom software solutions to Fortune 500 companies in Los Angeles, CA and Miami, FL for C# and VB .NET Winform and WebForm applications. We can provide a Web or Winform app that would take six programmers a year to complete in just days, thereby saving our clients, in some cases, millions of dollars.

To be able to do do this, I have written what I call "Model Applications" of MDI & SDI WinForms, Web Apps, and so forth that simply require changing the artwork and business logic.

I use Crystal Reports in my model apps for creating reports. This is the first part of a two-part article that will demonstrate how to implement a generic solution to using Crsytal Reports in Winforms and Web Apps.

Background

Crystal Reports is not easy to work with, and my experience has found that it has plenty of bugs and quirks. But, the big companies all seem to like it, so I had to develop a generic approach to using it.

One of the worst features of Crystal Reports is the way it handles report Parameters by presenting each parameter in a separate screen; clients really hate this! To solve this, this demo will show you how to present ALL of the parameters contained in a .rpt file in a SINGLE screen to the user.

This demo displays reports using two screens, a Reports Viewer and a Parameters Viewer. You could combine these screens; this is easy to do. These screens contain the following features:

Reports Viewer. This screen has a ComboBox that displays a list of reports that the user can select from. When the user presses the "Get Report" button, a modal window, called the Parameters Viewer, will be launched.

Parameters Viewer. This screen displays the parameters contained in the report selected in a datagrid that you dynamically add controls to to make selecting parameter values easier for the user. After setting the parameter values for the selected report, the user will close the Parameters Viewer and the Reports Viewer will display the selected report with the selected parameters.

Crystal Reports creates a binary file with an ".rpt" extension that contains ALL of the information you need to display any report. That is what you will use in this generic solution.

Select the .rpt file

Read the parameter information directly from the .rpt file

Build a table dynamically that displays all of the parameters in the selected .rpt report file.

The parameter table that you create dynamically also must contain controls that also are created dynamically to facilitate the user's selection of parameters, such as a date calendar, checkboxes, and so forth.

You must create validation controls dynamically from the parameter data that you read from the .rpt file.

Finally, you pass the parameter data into the Crystal Viewer and display your selected Crystal Report.

In the demo reports included, I didn't bother to connect to any data source because doing that is trival and the main point of this article is to show how to display the parameter data in a datagrid with selection controls dynamically. But, all of the code that does this is in place in the demo and will read the database information dynamically if there is any database information in the .rpt file.

Reading Parameter Data from .rpt Report Files

You started by pre-defining the columns of your Datagrid of Parameters as follows: Parameter, Kind, Value, Min, Max, and Prompt. You will add each parameter kind as a new row to your datagrid.

BooleanParameter

CurrencyParameter

DateParameter

DateTimeParameter

NumberParameter

StringParameter

TimeParameter

To dynamically build a datagrid of parameters, you read parameters from the .rpt file as follows:

For each parameter in the foreach loop, you add a row to your dynamic datagrid that has pre-defined columns.

Dynamically Adding Controls to Your Datagrid of Parameters

What is unusual about your datagrid of parameters is that you are adding each parameter as a new row instead of as a new column, which is what is more commonly done in datagrids. This means that I needed to implement a different approach to adding user controls. To accomplish this, I used the "GotFocus" event of the datagrid to selectively add/remove controls based upon the Parameter Kind listed in Column 2 of the datagrid.

For the puposes of this article, I implemented only three control types: DateTime, TimePicker, and CheckBox.

For example, when a user clicks on the datagrid, if Column 2 has a value of "DateTime," a DateTime Control will appear in the data cell for the user to select a "DateTime." I should point out that some programmers prefer using a "Radio Button" for Boolean values, but I prefer using a simple CheckBox for Boolean values that I implemented in the demo here. It should be obvious that you can implement any controls that turn you on or that a client requests.

The DateTime Picker Control

The DateTime Picker is a control that allows the user to select either a date, a datetime, or a time value. It provides two distinct GUI interfaces for a Calendar and a Time Spinner.

DateTime Control

Format

Description

h

12-hour - Hour with one digit if value is less than 10

hh

12-hour - Hour with a leading 0 if the value is less than 10

H

24-hour - Hour with one digit if the value is less than 10

HH

24-hour - Hour with a leading 0 if the value is less than 10

m

Minute - Minute with one digit if the value is less than 10

mm

Minute - Minute with a leading 0 if the value is less than 10

t

AM/PM - Letter A or P for the AM or PM section

tt

AM/PM - Letters AM or PM for the last section

To set the DateTime control as a Time Spinner, set the ShowUpDown Boolean property to "true," and change the Format property to a Time value. The Time Picker control is a spin button made of different sections: the hours value, the minutes value, the optional seconds value, and the optional AM/PM string. To change the time, the user clicks a section and uses either the mouse or the keyboard to increase or decrease that particular value. To change another value, the user must first click it and then use the spin button.

By default, the time displays using the H:M:SS AM/PM format. This means that the time uses 1 digit for the hours from 0 to 9, 1 digit for the minutes from 0 to 9, 1 digit for the seconds from 0 to 9, and AM or PM for morning or afternoon. To customize the way the time displays, first set the Format property to Custom. Then, in the CustomFormat property, use a combination of the following characters to create a custom format: hh:mm:tt

I set the format at run time by assigning the desired format to the DateTimePicker::CustomFormat property. By default, the control assumes the time of the computer when the control was added. If you want to set a different time, apply a Format combination to the Value property. In the same way, at any time, you can retrieve the time value on the control by accessing the Value property.

Beginner's Guide to Crystal Reports, Part I: Winforms

Points of Interest

File Exports

I included the ability to export the loaded report in a number of various file types, including:

Rich Text Document (RTF)

Portable Document (PDF)

MS Word (DOC)

MS Excel (XLS)

Crystal Report (RPT)

HTML 3.2 (HTML)

HTML 4.0 (HTML)

Optional XML File

I included a temporary XML file that you can optionally use to store parameter data.

Project Pathways

Load ALL of the Crystal Reports DLLs. These can be found at: C:\Program Files\Common Files\Crystal Decisions\1.1\Managed.

CrystalHelper Class

This class is a simple class that makes it easier to pass discrete parameter values to Crystal Reports. It allows you to further customize parameter options without having to re-write all of the code to pass parameters to Crystal Reports.

Calendar Auto Drop Down

If you want the calendar to drop down automatically when the calender field in the datagrid is clicked, you can send a Windows message "WM_KEYDOWN = 0x100" to update the button by using:

Win32.SendMessage(dtp.Handle, 0x100, 0x73, 0x3E0001)

Adjust Width of ComboBox DropDown

We automatically adjust the width of our dynamically generated combobox in the datagrid cell to the width of the longest element by using the combobox's "DropDown" event as follows:

About the Author

Bill SerGio

Need a VB .NET or C# .NET Web App or WinForm?
Let me quote you a FLAT price and we can deliver ANY project in LESS THAN ONE WEEK COMPLETED!
Our clients include over a dozen Fortune 50 and Fortune 500 clients in Los Angeles, CA.
We wrote a program that writes .NET applications using "Model Applications" and we can deliver ANY .NET application at a fraction of the cost and time.
Bill SerGio has written, produced and directed over 100 Famous Infomercials that starred over 100 Famous Celebries. He is listed in Marquis Who's Who in America(that's the book you CAN'T pay to be listed in!) as well as Who's Who in Advertising.
My company can buy the BEST infomercial time at the LOWEST PRICES -- CALL ME! We can produce an infomercial with a famous celebrity host at NO COST to your company to sell your product if we like your product!
email us: tvmogul1@yahoo.com